Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so safety is covered. The description adds real behavioral value beyond them by disclosing the breadth of the payload (production history depth, fracture jobs, trajectory), which lets an agent anticipate a large response and plan around it. It does not cover pagination or behavior when no identifier is supplied.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the access pattern before the payload list, and the example earns its place by pinning down the identifier syntax. The middle enumeration is dense but each item is a distinct data category rather than filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so the description's enumeration of returned data is partly redundant but harmless. The notable gap is that zero parameters are required, yet the description never says what happens if neither sigla nor idpozo is provided, nor what max_rows controls.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is only 33%, so the description carries extra burden and partially meets it: the worked example clarifies the sigla string format ('YPF.Nq.LCa-1001(h)'), which the schema only describes as 'Well code'. But idpozo is given no meaning at all and max_rows is never mentioned, even though it governs the response size implied by the long data enumeration.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Starts with a specific verb+resource and cardinality ('One well by idpozo or sigla'), then enumerates exactly what the caller gets back: registry data, IP30/90/180, cumulative volumes, GOR, water cut, 36 months of production, fracture jobs, trajectory. An agent can distinguish this from the plural, filter-oriented sibling query_wells without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies the usage context (you must already know a specific well identifier) and supplies a concrete sigla example, which is genuinely helpful. However, it never states when to prefer this over query_wells or resolve_entity, nor any prerequisite or exclusion, so usage is left to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.